Oxy/Propane torch question

[eseemann]

Good Morning All,

 

I was looking around YouTube for videos on O/P cutting and I start watching a video where this guy takes a regulator off the acetylene tank and puts it on the propane tank. Now I use an acetylene reg for my propane so that is nothing new but I have always been told that you can use a acetylene reg on propane but once you do you should not use it on acetylene again. I have also been told that acetylene reacts poorly with oils or products such as Liquid Wrench, Kroil, PB-Blaster, or Break-Free.

 

The guy I got my portable O/A kit from told me a story about getting a very old acetylene tank from his Dad's barn and trying PB-Blaster on the valve then called a buddy for advise. The buddy's advice was to move the tank away from the barn and run!

 

Have you good folks heard the same cautions and what can you tell me about these warnings?

 

 

[jmccustomknives]

Well, as far as the last part I've never heard such but it is a huge no no to use any oil or oil based products on any high pressure gasses.  I've seen many regulators that have blown apart from as little as a spider that crawled off in it.  It's always oxygen that is reactive in that manner.  Acetylene is another animal all together.  Now as far as changing from ac to pr and back technically it works(I've done it) but since propane will break down rubber it could ruin the diaphragm in the acetylene regulator and hoses.  The ac reg is also designed not to exceed 15psi while propane can be (and at times must be) ran higher.

If you go to Victor Technologies website you'll find that info, someone here may already have a link. 

[eseemann]

Thanks JMC,

 

There is as much lore as data in the world crafting of all kinds. I have an MC tank so the reg I use for propane never needs to go on to the acetylene take since the MC tank has it's own reg. I just got a small hobby size campbell hausfeld stick welder from Ebay and I think I will be using that for most small welds and with the small O/A rig as the back up. I find that brazing has taken care of most of my needs up to this point and that works like a charm with O/A and O/P. I figured if I wanted to get a small bundle together for a pattern weld a bronze braze might not be the best idea when the braze melts before the first weld. :huh:  

Thanks again.,,

 

Ernest

[ThomasPowers]

If your regulator is marked "for all fuel gasses" then there is no problem swapping it back and forth. As mentioned propane will eat the seals on an acetylene regulator not built for all fuel gasses and you would not want to use a propane specific regulator on acetylene as they generally would allow you to go to pressures that can cause explosions in Acetylene. (Acetylene just doesn't play nice---it can exothermically disassociate even without O2!)

Oxygen is deadly around *any* oils or organics in the regulator or fittings. As long as they are not eating the seals in the regulator then they should not be a major issue with fuel gasses.

[ThomasPowers]

Note that flashback arrestors should be a part of ANY acetylene system; however if propane is not combined with high pressure O2 an explosion cannot propagate into the propane tank as it does not burn/explode without the presence of oxygen. It is possible with leaky fittings/hoses to get a burnable mix after them being left alone awhile but that only involves the hose.

[eseemann]

Thomas,

 

All very good points. My reg is from a cheap kit so I will end up needing to repare or replace sooner or later. I do have the flashback arrestors and I have heard bad things about letting the magic smoke out of the acetylene bottle. BooM!!